Process of devulcanizing rubber.



.m 'rnn a m MTENT WWW? samurai. E. rman, or Anson, onto, nssrenon TO THE EMPIRE RUBBER CoMPANY, A

. CORPORATION or 02110; a v l To all tv/wm it concern:

. Two I ess: Eirshthdiscovery that a certain kind l PROCESS DEVULCANIZING RUBBER.

Specification of Letters Patent. Pat ted A 11. 1916 i No Drawing. Application filed December 7 1911, Serial No. $64,372. Renewed December 2219M. Serial h 4 Be-it known that: I, SAMUEL E. ALLnN, of Akron county of Summit, and State of Ohio, a. cit zen of the United States have inventednew and useful Improvements in the Process of Dev'ulcanizing Rubber, of which the following is a specification.

This invention consists in a new and im- --proved-process for devulcani'zing rubber producing a new and improved product.

d scoveries are involved in this procof oil has the capability of devulc'anizing that ofresin .oil; in other words, between rubber and, not only so, but even to an un-' precedented degree of eiliciency. Second, the d scovery that'this may be availed of on vulcani'zed goods '1 containing fiber, with the concurrent action of a fiber destroying agent in a single operation.

The oil employed in my process is a distillate of pine wood having a specific gravity between that of -oil of turpentine and about .88 and 96 at'15.- 0.. More specifically,

the oil that I have employed is about from [.93, to, .95 specificgraVit y and may be obtained as a distillate from the stumps of long leaf pine K trees '(Pinus ling according to'the palustrz's) b'y' distilwell known resin or otherbath process, in whic'h'the bath has a higher boiling point than the distilling temperature' of the oil and subsequent redistillation. This oil is to befo'und on the market. and may be 'further fact that the greater part of its bulk in a I dry stillwill distil over at a temperature between about 200 and 220 O. The preferable specific gravity is from .935 to945 at15 C.

all;

In devulc'anizing rubber fiber, known in the trade as pure gum stock, I proceed-asifollows:. The rubber is ground so as to pass through a screen of 3 to 5 mesh per inch the rubber. The'said .oil isdistributed over the surface and mixed either by hand or machinery. The proportions are about as follows? 200 lbs. pure gum stock, 00 lbs. water, 17 lbs. said oil. The mass is dumped into a covered devnlcanizing tank which is run into adevulcanizing oven where it is inclosed so as to maintain pressure and where it is allowed to remain for about 15 hours at a temperature and pressure coridentified by the.

containing no and placed in a mixing tanln ater is added suflicient to just submerge responding with about 100 'lbs'. steam pre ssure (327 I applied either by admitting v the steam nto a surrounding steam jacket or directly into the deviilcanizing oven. The

ceed 'as follows: The rubber is ground so I as to pass through a" screen of 3 to 5 mesh per inch and placed in a covered mixing "tan'k. A'solut-ion of sulfuric acid in proportions as below is added; The said-oil is dis- "ti'ibuted over the surface and: mixed by -machinery or hand. The remainder of the process is the same as with the pure gum stock.

'The' proportions are as follows: ;200 lbs.

ground tires, 800 lbs. water-. 2 gallons sulfuric acid. 3 gallons said oil. p

' In jdevulcanizing rubbercontaining more or less wool fiber mixed with the cotton,- such as 'old rubber boots and shoes; I proceed. as follows: The rubber is ground so as'to pass through a screen of 3 to 5 mesh per-inch and placed in a covered mixingtank submerged with 21 2% solution of sulfuric acid and al lowed to stand for 12 hours at ordinary tem perature. The said oil is thendistributed over the surface and mixed. Then more'sulfuric acid 1s added. The rema nder of the process isqas before. The proportions are as follows 200 lbs. ground boots, and shoes, 600' lbs. water acidulated with sulfuric acid, 2 gallons sulfuric acid, 3 gallonssaid v Instead of a devulcaniz ing'ta nl; in a stationary deyulcanizer, a double acke'ted res volving devulcanizer may be employed-with the. heat and pressureabove specified. v

I d not limit myselfto sulfuric acidv as the fiber removing agent, equivalents being possible. Excepting when expressly specified in particular claims jI do notlimit myself to oil of long leaf Variety of pine, nor

tioned T101 the oil obtained 'by th gbath process.

I preferto apply the heat in the process of devulcanizi-ng by passing the current of to the more particular specificgravitiesmen- I tank containing the. mass and thereby applies the heat to the mass from every direcv tion. The cover of the devulcanizing tank that I prefer to employ is a loose cover not necessarily excluding the steam.

What I claim as'new and desire to secure by Letters Patent is:

1. The process of devulcanizing rubber which consists in subjecting the same to a wood.

The process of devulcanizing rubber which consists in subjecting the same to a bath containing oil of between .88 and .96 specific gravity distilled from pine Wood in a. bath of liquid having a boiling point above 200 C.

4. The process of devulca-nizing rubber.

which consists in subjecting the same to a bath containing oil of about from .93 to .95 specific gravity obtained by distilling pine wood.

- 5. The process of devulcanizing rubber which COIlSlStFRiIl subjecting the same to a bath containing oilof about from .93 to .95 specific gravity obtained by distilling long leaf pine wood. f v

6. The process of devulcanizing rubber which consists in subjecting thesame to a bath'containing oilof about from .93 to .95 specific gravity obtained by distilling pine,

wood in a bath of liquid vol'atilizing at above V fiberizing rubber which consists in subject- 7. The process of devulcanizing rubber which consists in subjecting the same to heat and pressure in a bath containing water and oil of between .88 and .96 specific gravity distilled from pine wood. j 8. The process of devulcanizing an'd defiberizing rubber. which consists in subjecting the same to a bath containing water and. a fiber destroying agent and oil of between .88 and .96-specific vgravity'distilledfrom pine wood. V 9. The process of de'v ulcanizing anddefi berizing rubber which consists-in sub ecting the'saine to a bath containing a fiber. destroying agent and an oilot' between .88 and' .96 specific gravity obtained fron p ne wood. 10. The process of devulcanizlng'and dc fiberizing rubber which consists in subjecting the same to a bath containing a defiberizing agent andan oil of about .93 to .96

specific gravity obtained frompine wood.

, 11. As a new article of manufacture, the product which may be obtained by devulcanizing rubber in a bath containing oil of about from .93 to .96 specific gravity distilled-from pine wood.

12. The process of devulcanizing rubber which consists in subjecting the same to heat and pressure-in 'a bath containing oil obtained from pine wood which oil in a dry still will, in greater part, distil over at a temperature between about 200 and 220 C.

13; The process of devulcanizing rubber which consistsin subjecting the same to heat and pressure in a bath containing oil obtained from pine wood which oil in a dry still-will; in greater part, distil over at a temperature between about 200 and 220 C. and having a specific gravity between .90 and .96-at 15 C.

14. The process of devulcanizing rubber which consists in subjecting the same to a bath containing pine oil obtained from pine wood.

15 The process of devulcanizing rubber which consists in subjecting the same to a bath containing oil obtained from pine Wood and having a specific gravity between that of turpentine and resin oil.

' 16. The process of dev'ulcanizing rubber which consists in subjecting the same to a bath containing oil obtained from pine wood and having a boiling point between approximately 200- vand 220 C.

17. The process of devulcanizing and deing the same to a bath containing a fiber 'destroying agent and pine Oll.

18. As a new articleof manufacture the f product which may be obtained by devulcan- 'izing rubber in a bath COHtQiIIiDg'PIIIB oil obtained from pine wood I 19. The process of devulcanizing:rubber which consists in subjecting the same to heat and pressure in abath containing water and pine oil obtained from pine wood;

In testimony whereof, I .have-. hereunto signed my name in the presence of twmsubscribing Witnesses";

w SAMUEL E. ALLEY.

VVitnes ses J n" E. Tarnou, Ginoner I). GILMORE. 

